Pneumatic cleaning system



Aug. 19, 1969 JQKLAEU| 3,461,693

PNEUMATIC CLEANING SYSTEM 2 Sheets-Sheet 1 Filed Sept. 7. 1967 FIG2 34 w R E Y O A E T L N N K R E 0 W I M M Aug. 19, 1969 H. J. KLAEUI PNEUMATIC CLEANING SYSTEM Filed Sept. 7, 1967 2 Sheets-Sheet 2 INVENTOR HANS J. KLAEUI ATTORNEY United States Patent 3,461,693 PNEUMATIC CLEANING SYSTEM Hans J. Klaeui, Shrewsbury, Mass, assignor to Crompton & Knowles-Malimo, Inc., Worcester, Mass, 21 corporation of Massachusetts Filed Sept. 7, 1967, Ser. No. 666,209 Int. Cl. D04b 35/32 U.S. Cl. 66-168 7 Claims ABSTRACT OF THE DISCLOSURE A pneumatic cleaning system for Warp knitting machines in which blower ducts are made part of the sinker construction with openings in close proximity to the knitting needles and sinkers, and suction ducts are placed so as to draw lint laden air from the needle and sinker area.

This invention relates generally to apparatus which constitutes a cleaning system for textile machinery such as knitting machines and the like. More particularly, the invention relates to apparatus for preventing foreign matter such as lint generated by operation of the knitting machine from being deposited on critical areas such as the knitting needles and sinkers. The invention also relates to apparatus for collecting and removing the lint from these areas.

Textile manufacturers have always experienced the problem of deposits of lint being formed during operations of fabric formation. This lint results from small fibers breaking off from yarn strands every time the strands move from a supply source to a mechanism which incorporates them into the fabric. The mill becomes saturated with lint which eventually settles on the textile machinery. Eventually the machine builds up a substantial coat of lint which becomes a serious problem in some critical areas such as the knitting needles on a Warp knitting machine. The spaces between the needles and various guiding elements such as sinkers are very small and any accumulation of lint in these areas may interfere with the proper operation of the knitting needle.

The lint sticks tenaciously to any surface to which it is deposited because of sizing thereon and the high relative humidity normally maintained in a textile mill. In a relatively short time, the lint collects in a quantity great enough to interfere With operation of the knitting 'machine so as to require the machine to be shut down and cleaned. Some of the large conglomerations of lint may fall away from the machine and be incorporated into the fabric thereby resulting in an inferior product.

Prior art system have ranged from hand held air hoses and overhead traveling blower units to rigid vacuum hoods mounted on the machines. Blower units have the disadvantage of allowing the blown pieces of lint to resettle on the machine or on other machines. Vacuum systems on the other hand remove a great deal of free lint but cannot efficiently prevent all lint from accumulating on the machine. Combined blowing and suction systems have been used on other types of textile machines such as looms. In one example of this type, lint, falling from a specific area such as drop wires, is collected on channels whereby air is blow from one end to the other end where there is a suction means for Collecting the lint. As the air moves from one end to the other it gathers the lint which has accumulated on the channels to be collected by the suction means. Systems of this type merely collect and remove some of the lint in the vicinity of a particular structure but do not prevent the accumulation of lint thereon.

The present invention is specifically adapted to a warp knitting machine and overcomes the objections encoun- 3,46l,693 Patented Aug. 19, 1969 t ered with prior art systems. The invention comprises air outlet ducts which are incorporated into the structure of the machine and are connected to a source of air at superatmospheric pressure. These ducts have openings adjacent the critical area of the knitting needles and sinkers through which a continuous blast of air is directed to the needles and sinkers to prevent lint and other foreign matter from accumulating thereon. Intake ducts which are connected to a source of air at subatmospheric pressure have openings located in the vicinity of the knitting needles and sinkers to collect the airborn lint, The sinker bars are modified to also function as outlet ducts.

It is therefore a general object of the invention to provide a simple pneumatic means for efficiently and continuously blowing a stream of air against the knitting needles and sinkers of a warp knitting machine to prevent accumulation of lint and foreign matter thereon.

Another object of the invention is to provide means for pneumatically collecting the lint and foreign matter which is prevented from accumulating on the machine.

Still another object of the invention is "to incorporate the outlet ducts as part of the structure of the knitting machine so that it will not interfere with the operation of the machine.

Other objects and the details of that which is believed to be novel will be clear from the following description and claims taken with the accompanying drawings, in which:

FIGURE 1 is a diagrammatic side elevation view of the loop forming mechanism of a warp knitting machine with the invention applied thereto, parts being shown in section;

FIGURE 2 is a horizontal section on line 22 of FIGURE 1 showing the outlet duct openings beneath the knitting needles;

FIGURE 3 is a diagrammatic view of the pneumatic system;

FIGURE 4 is an enlarged view similar to FIGURE 1 showing a modification of the blower duct.

Referring to the drawings, there is shown a warp knitting machine generally indicated by the reference numeral 6. The machine can be of the type shown for instance in U.S. Patent No. 3,030,786. Referring specifically to FIG- URE l, the machine has a frame 8, knitting needles 10 and a knitting thread guide 12. The particular type of knitting needle shown has a hook 14 like a crochet needle and a sharp point 16 for penetrating the material M to be stitched. The needles are reciprocated left and right, as shown in FIGURE 1, through the material M. While the knitting needles are in their forward stroke (to the right in FIGURE 1), thread guides 12 are moved in such a way so as to wrap knitting yarns Y around the hooks 14. As the needles 10 move to the left, closing wires 18, mounted on a bracket 20, slide in grooves 22 (see FIGURE 2) of the needles. This closes the hooks 14 of the needles to securely retain knitting yarns which are inserted within the bight of the hook. The material M can be yarns, scrim or a system of loose fibers in a non-woven batt. The particular type of knitting arrangement shown is described in greater detail in the aforementioned U.S. patent, but it is to be understood that the invention could be applied to other types of knitting mechanisms as well.

To hold the layer of material M against the action of the needles, a comb-like structure is arranged in back of the material. This structure comprises a bracket 24 containing a row of needles or tines 26 which point downward and are arranged so as to permit needles 10 to penetrate between adjacent tines. Opposite thereto is another comb-structure which includes a bracket 28 for supporting tines 30 which point in an upward direction. The material M being stitched must be held in position by a suitable support when the needles 10 are withdrawn from the material together with loops formed from the knitting yarns Y. The support includes a series of sinker bars 32, each of which support a plurality of sinkers 34. To facilitate the insertion of material at the beginning of the operation, the upper margin of sinkers 34 are preferably bent at 35 so as to enlarge the opening between brackets 24 and sinker bars 32.

Bars 32 are mounted on outlet ducts 36 by screws 37. Ducts 36 are in turn mounted on a main outlet duct 48 by bolts 38. Main outlet duct 48 is mounted to frame 8 by bolts 39. Outlet ducts 36 have elongated openings 40 (see also FIGURE 2) which appear just beneath the path of knitting needles and adjacent sinkers 24.

Mounted on a horizontal portion 42 of frame 8 by bolts 43 are intake ducts 44 with openings 46.

Outlet ducts 36 have internal passageways 47 which are pneumatically connected to main outlet duct 48 which represents a source of air at superatrnospheric pressure. Intake ducts 44 are connected to a main intake duct 49 which represents a source of air at subatmospheric pressure.

The upper rearward edge 50, which defines part of the opening 40 of each duct 36, extends upwardly slightly above the opening to a point just below the plane of travel of needle bar 52. The opposite or forward edge 53 of each opening 40 is inclined forwardly and upwardly toward sinkers 34. This construction enables the air which is blown through the openings 40 to clean the forward or hook portions of the needles when they are in the rearward position (to the left in FIGURE 1). When the needles are in the forward position, bar 52 lies over the top edge 50 and effectively blocks off the flow of air to the rearward part of the machine and with the help of the inclined forward edge 53 deflects the air blown toward sinkers 34 as shown by the flow arrows in FIGURE 1.

In this way, the critical areas of the knitting needles and sinkers are given rapidly pulsating blasts of air to prevent any accumulation of lint thereon. The sinkers, and particularly the bent portions 35 thereof, help to deflect some of the air coming through outlet openings 40 towards openings 46 of intake ducts 44. There is created a general turbulence in the area between the knitting needle elements and openings 46 so that the lint laden air therebetween is drawn into the intake ducts. The lint containing air is then drawn into main duct 49.

If desired, a single pump means, indicated at 55, can supply air at both subatmospheric and superatrnospheric pressure as shown diagrammatically in FIGURE 3. Referring to that figure, pump 55 supplies air at superatmospheric pressure to main blower duct 48 and outlet ducts 36. This air is drawn from main suction duct 49 through a filter and accumulator means 54 thereby creating subatmospheric pressure in duct 49 and suction ducts 44.

Referring to FIGURE 4, the sinker bars and blower ducts are shown as single units and are identified by the reference character 56. Bolts 58 anchor units 56 to duct 48. Units 56 have internal passageways 60 which pneumatically communicate with main duct 48 and which are the equivalent of passageways 47 in FIGURE 1. The up per portions of units 56 are formed into sinkers 62 which are the equivalent of sinkers 34. Each unit 56 has a rear ward edge 64 and a forward edge 66 which define an opening 68. Edges 64 and 66 are the equivalent to edges 50 and 53 respectively and serve to deflect air emerging from opening 68 toward sinkers 62 when the knitting needles are in the forward position.

It will be seen therefore from the disclosure that the invention offers an efficient and effective means to prevent accumulation of lint on the critical areas of the needles and sinkers in a warp knitting machine.

It will of course be apparent to those skilled in the art that if necessary, other shapes of the openings 40 and 68 differing from that shown may be used. Other aspects of the disclosure may be modified without departing from 4 the spirit and scope of the invention as defined in the appended claims.

What I claim and desire to secure by Letters Patent is:

1. In a warp knitting machine having a row of knitting needles and a row of sinkers mounted in sinker bars, a pneumatic cleaning system comprising:

(a) a source of air at superatrnospheric pressure;

(b) outlet ducts disposed on said machine and connected to said source, said ducts having openings arranged along substantially the entire length of said row of needles for directing continuous streams of air across said needles and sinkers, thereby preventing the accumulation of foreign matter on said needles and sinkers;

(c) a source of air at subatmospheric pressure; and

(d) intake ducts disposed on said knitting machine and connected to said source of air at subatmospheric pressure, said ducts being located in the vicinity of said sinkers and needles, whereby said air which is blown across said sinkers and needles, together with foreign matter suspended therein, is drawn into said intake ducts.

2. In a warp knitting machine as described in claim 1 wherein said outlet ducts support said sinkers on one side thereof.

3. In a warp knitting machine as described in claim 1 wherein said knitting needles are mounted in a needle bar which, together with said needles, reciprocate rearwardly and forwardly over the openings of said outlet ducts, each of said ducts comprising:

(a) a rearward edge defining the rearward part of the opening of said duct and which extends to a point just below said needle bar;

(b) a forward edge defining the forward part of the openings of said ducts and which is inclined outwardly toward said sinkers, whereby the streams of air from said ducts will be blocked by said rearward edge and guided by said forward edge toward said sinkers when said needles are in the forward position.

4. In a warp knitting machine as described in claim 1 wherein said outlet ducts and sinker bars comprise single units wherein the upper portions of said units are formed into sinkers.

5. In a warp knitting machine having a row of knitting needles mounted in a forwardly and rearwardly reciprocating needle bar and a row of sinkers mounted in sinker bars, a pneumatic cleaning system comprising:

(a) a source of air at superatrnospheric pressure;

(b) outlet ducts disposed on said machine and connected to said source of air at superatrnospheric pressure for directing air at superatrnospheric pressure across said needles and said sinkers, said ducts comprising:

(1) a rearward edge defining the rearward part of an opening for said duct, said edge being located just below said needles and needle bar at a point where the rearward part of said opening is substantially obstructed by said needle bar when said needles are in their forward position;

(2) a forward edge defining the forward part of said opening, said forward edge being inclined outwardly toward said sinkers for directing air towards said sinkers, whereby air will be blown across said needles when the needles are in their rearward position and whereby said air will be blocked by the rearward edge of said ducts in cooperation with said needle bar and guided by said forward edge toward said sinkers when said needles are in their forward position.

6. The knitting machine as described in claim 5 where in said cleaning system further comprises:

(a) a source of air at subatmospheric pressure;

(b) intake ducts disposed on said knitting machine and connected to said source of air at subatmospheric pressure, said ducts being located in the vicinity of said sinkers and needles whereby said air which is blown across said sinkers and needles, to-

gether with foreign matter suspended therein, is drawn into said intake ducts.

7. In a warp knitting machine as described in claim 5 wherein said outlet ducts and sinker bars comprise single units wherein the upper portions of said units are formed into sinkers.

References Cited UNITED STATES PATENTS 6 2,662,626 12/ 1952 Fletcher 139-7 2,846,860 8/ 1958 Shortland 66-168 2,919,566 1/1960 Felker 66-168 3,220,223 11/1965 Schmidt 66-168 3,311,135 3/1967 Maguire et al. 139-1 3,267,970 8/1966 Maguire et a1. 139-1 3,269,151 8/1966 Abram et a1. 66-168 3,274,803 9/ 1966 Schmidt 66-168 FOREIGN PATENTS 1,023,846 3/ 1953 France.

1,281,650 12/ 1961 France.

1,061,943 7/ 1959 Germany.

1,113,786 9/1961 Germany.

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